Saunders coatbs



lS. COATES.

Gas Retrt.

No. 18,134. 'l l 'Patentedept 8, 1857.

AM. PH-OTO-LITHILCO. NJMUSBORNE'S PRDCESS) UNITED sTATEs PATENT oEEIoE.

SAUNDERS COA'IES, OF NEV YORK, N. Y.

ens-RETORT.

Specification of Letters Patent No.

' nexed drawing, making a part of this specilication, in which theligure is a transverse vertical section of a retort-that is to sayln thepot or caldron shaped retort, as heretofore constructed for thegenerating of oleant gas, there has existed considerable ditliculty inkeeping them in good order and in continued wear, in consequence ofwhich they have frequently to be replaced. This defect has been hithertodeemed inseparably connected with this plan of making gas, for therequisites are that the vessel shall sustain a high degree of heat;shall have capacity also for storing, as it were, the heat, and shallresist as far as possible the oxidizing eect growing out of thecombustion of the residuum left by the gas making materials (oils, &c.)One prime cause of t-he 4destruction of the retort has been the methodor forni of constructing them so as to act as a magazine for heat, viz,by casting the bottom of much greater thickness than the sides-becauseit is important to keep the temperature as equable as possible, whichwere the metal alike thin would not be the case, since whenever the irewas renewed the retort would be cooled down, and this even by theopening of the furnace door. It often occurs therefore, in consequenceof this extreme thickness, that the bot-toms crack from yunequalexpansion, and thus the retort is ruined. A next defect is the saggingof the bottom from overheating such a mass of metal, and which not onlydiminishes the gas generating properties, by collecting the oil in amass in the center, but also increases the carbonaceous deposit, causinga loss in the quantity of gas as well as prolonging the operation. By myimprovement all these defects are obviated, while at the same time thegas generating power of a retort of given size is largely increased.

The nature of my invention consists in a peculiarly arranged orconstructed false bottom, which bottom is composed of two dis- 1s,134,dated september s, 185'?.

similar metals-viz, one which is fusible at a comparatively lowtemperature, in combination with one fusible only at a much highertemperature, and thus I am enabled to cast the retort with the samethickness of metal throughout, whereby the wear is prolonged, while thequantity of metal required to act as a reservoir of heat for maintainingsteadiness of the gas generating, is also secured, without risk to saidretort, and whereby also the interior is protected from the oxidizingagencies due to the cleaning of the same by burning out.

In preparing my false bottom, I in the first instance pour in the moreeasily fused meta-l, having first melted it. This metal may be lead,which although a bad conductor has considerable capacity for heat. Uponthis I place the other metal and which I prefer to be iron. A plate ofsay half an inch, lnore or less, in thickness is cast to lit the bottomand this is laid upon the lead, as shown in the figure wherein Arepresents the retort, (b) the stratum of lead, and (c) the iron plateplaced thereon.

The operation is as follows: The retort is placed in the stove andconnected with the rest of the apparat-us as usual. Fire being raised,when the retort has attained the proper degree of heat for the admissionof the oil, the lead will have become melted and the iron plate be foundfloating upon the top'. The process then goes on as usual. I have foundthat the product of gas from a given quantity of oil has been muchlarger than by the old way-that the gas is also` better, being moreuniform in qualitythat the retort does not change its shape or crack asbefore-but even if its shape should be changed by the sagging of thebottom the surface receiving the oil would still be level-and lastly theinterior is protected, since the iron plate upon the lead is the partnow destroyed, and that part is readily and cheaply replaced whenneeded.

I am aware that lead alone has been poured into such gas retorts, butthe action is found to retard the gas generating. The mass soon becomesso filled with bubbles of gas that the processafter a short, intervalalmost ceases; its use therefore has never been continued, as it was amore serious evil than the one it was intended to remedy.

I claim- In Witness whereof I have hereunto sub- Forming a false bottomfor gas retorts, scribed by name. from metal of dissimilar degrees offusibility, viz, one such as lead, in combination SAUNDERS COATES 5 withone, such as iron, resting upon the Witnesses:

easily fusible metal, substantially in the J. P. PIRSSON,

manner and for the purpose described. S. H. MAYNARD.

